Covid-19: The facts
It was New Year’s Eve 2019 when China Health officials reported to the World Health Organisation (WHO) offices that a pneumonia of unknown cause was detected in Wuhan. There was a rapidly growing number of people suffering from a dry cough and fever before developing pneumonia. The new virus was named SARS-CoV-2, or as we now know it, covid-19 – Coronavirus 2019.
Since then, it has been spreading rapidly. The current count is 529,070 cases worldwide, with 128,620 who have recovered and 24,862 deaths. In the UK, the figures currently stand at 11,658 who have tested positive to the virus, 135 who have recovered, 10,945 active cases and 578 deaths. However, these numbers are changing on a daily basis.
What is a coronavirus?
It is part of a family of viruses that cause disease in animals. They are named based on their appearance under the microscope; this virus presents with pointed structures on its surface that resemble a corona, or crown.
There are seven strains, including covid-19, that have made the jump from animals to humans. Majority of the types only cause flu-like symptoms, however the two strains that have caused major issues are Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Covid-19 is thought to have a much lower fatality rate compared to MERS (30%) and SARS (10%), however it is much more infectious, hence its overwhelming spread.
Where did it originate?
Studies from China suggest covid-19 mutated into two strains; one being more aggressive than the other. The source is believed to be a "wet market" in Wuhan. This market sells dead and live animals that wouldn’t usually be found in close contact otherwise. These markets are densely packed, with poor hygiene and animals are often butchered on-site. This creates an environment that poses an increased risk of viruses jumping from animals to humans.
It is thought that the animal source of covid-19 was a bat before the virus went to a pangolin and subsequently to humans. All three of these carriers would have been in contact with each other in the Wuhan market.
How is it spread?
Similar to other viruses that cause colds and flus, covid-19 is spread via droplets. The firm belief is that the disease spreads via "close contact", classified as spending more than 15 minutes within two metres of an infected person.
Covid-19 vs The Spanish Flu vs Swine Flu vs SARS
It is still early to understand the global impact that covid-19 will have.
The most devasting flu pandemic in modern history still remains the Spanish Influenza in 1918, causing up to 100 million deaths. In comparison, the Swine flu in 2009 was reported to have caused up to 575,400 deaths and the outbreak of SARS was much smaller, causing up to 800 deaths.
Is there a test for Covid-19?
Testing involves a molecular assay-based detection of the nucleic material (RNA) within the virus. The presence of this nucleic material in a swab sample (usually of the throat) indicates infection, whereas its absence indicates a negative result. This takes time to get a result as the tests have to be sent to the lab.
The new test the UK Government is hoping to begin distributing next week is known as a rapid lateral flow test to detect immune markers of coronavirus. It is designed to be a finger-prick test that uses a tiny capillary blood sample and takes up to 10 minutes to get a result. It is similar to a pregnancy test but uses blood instead of urine.
In general, lateral flow tests use monoclonal antibodies that are specific to what we are testing for, which may be a protein or other molecule, to give a positive or negative result on a test strip.
The new coronavirus lateral flow test uses antibodies that are specific Immunoglobulin M and G (IgM and IgG) that are produced by infected individuals in response to the virus. Immunoglobulins are normally produced by the immune system in response to bacterial or viral infections and act to ‘flag’ the pathogen, so that other immune cells can detect and kill it.
The IgG/IgM that the test detects are specific covid-19, so a positive result would indicate the patient has contracted the virus.
Since there are two, IgM and IgG, there are two test lines on the strip. Only one test line needs to be seen for a positive result.
Is there a cure?
There is no specific treatment. However, studies using hydroxycholoquine and azythromycin have shown potential. There is a drive to develop a vaccine, but it is complicated as the virus has mutated into a second strain.
Dr Ravi Brar is medical director of sk:INSPIRE Medical Aesthetics. He graduated from Guys and St Thomas Medical School and is a member of the Royal College of General Practitioners. He has a special interest in dermatology, having completed postgraduate studies in Clinical Dermatology from Queen Mary University London, with a distinction. His patient-centred ethos is to naturally enhance and define, helping his patients to look and feel their best. He prides himself on a holistic approach, ensuring that the patient is also educated on their skin.
